Disclosed is a multi-tip extrusion apparatus and design methodology whereby
a single extrusion head having approximately co-planar, fixed-position
dispensing tips is used in a three-dimensional modeling machine to deposit
multiple types of materials from distinct material supply sources. The
tips are spaced apart a distance great enough so that a road of material
extruded by a leading one of the tips will cool and shrink from the plane
of the tips so that it is not smeared by contact with a trailing one of
the tips.
